Heats of Dissolution of Thiamine Disulfide-Fatty Acids Complexes in Ethanol

概要

論文の詳細を見る
The heats of dissolution (ΔH_d) of thiamine disulfide (TDS)-fatty acids (FA) complexes, (FA)_6 (TDS), were measured at 310.15 K in ethanol using a calorimetric technique, where the FA are tetradecanoic acid (C14), pentadecanoic acid (C15), hexadecanoic acid (C16), heptadecanoic acid (C17) and octadecanoic acid (C18). The values of ΔH_d were 432.8,475.0,493.3,541.0 and 558.5 kJ mol^<-1> for (C14)_6(TDS), (C15)_6(TDS), (C16)_6(TDS), (C16)_6(TDS), (C17)_6(TDS) and (C18)_6(TDS), respectively. The values of ΔH_d of (FA)_6(TDS) increased by increasing the carbon numbers (n) of the constituent fatty acids. However, the plots of ΔH_d of (FA)_6(TDS) against n showed a zig-zag pattern which indicates an upward convex at an odd-numbered position, while the plots of ΔH_d of FA against n indicate a single line pattern.The differences between ΔH_d of (FA)_6(TDS) and ΔH_d of (6FA+TDS) were 23-37 kJ mol^<-1> for even-numbered FA and 33-41 kJ mol^<-1> for odd-numbered FA, indicating a stronger binding force for (FA)_6(TDS) formed from odd-numbered FA than those formed from even-numbered FA. Furthermore, the estimated values for the binding force between FA and TDS are very small, leading to a conclusion that (FA)_6(TDS) is a clathrate (or an inclusion compound) formed by van der Waals forces and hydrophobic interactions between FA and TDS.
公益社団法人日本薬学会の論文
1991-06-25